Conventional technology for a mirror system that confirms the area to the side of a vehicle is already known. (Refer to Unexamined Japanese Patent Application Publication No. 2004-196218.)
For this type of mirror system, in addition to a side mirror, a prism or fresnel lens is provided on the window glass in front of the side window so that the front area of the side of the vehicle, in other words the blind spot, can be visually confirmed.
However, for such a mirror system, since a prism or a fresnel lens is provided on the window glass, the field of view, which is the portion that can be directly viewed through the window glass, would get obstructed by the prism or the fresnel lens.